Tuesday, January 30, 2018

January 30, 2018 Tuesday

Bedtime Story 


Note C of Ada Lovelace - 2


We are continuing with the Note C of Ada Lovelace in the treatise of Menabrea: “Sketch of the Analytical Engine” that was translated into French by Ada Lovelace and published along with her notes in 1842.

“This process is alluded to by M. Menabrea (as we shall see later when we get back to the writing of Menabrea), and it is a very important simplification.

It has been proposed to use it for the reciprocal benefit of that art, which, while it has itself no apparent connection with the domains of abstract science, has yet proved so valuable to the latter, in suggesting the principles which, in their new and singular piece of application, seem likely to place algebraical combinations not less completely within the province of mechanism, than are all those varied intricacies of which intersecting threads are susceptible.

By the introduction of the system of backing into the Jacquard-loom itself, patterns which should possess symmetry, and follow regular laws of any extent, might we woven by means of comparatively few cards.

Those who understand the mechanism of this loom will perceive that the above improvement is easily effected in practice, by causing the prism over which the train of pattern-cards is suspended to revolve backwards instead of forwards, at pleasure, under the requisite circumstances; until, by so doing, any particular cards, or set of cards, that has done duty once, and passed on in the ordinary regular succession, is brought back to the position it occupied just before it was used the preceding time.

The prism then resumes its forward rotation, and thus brings the card or set of cards in question into play a second time.

This process may obviously be repeated any number of times.”      

Here Lovelace makes an attempt to describe how the card system of the loom can be used in the engine to carry out repeated mathematical operations.

Now we will go back to Menabrea where he continues to describe in greater detail how the card system was proposed to be used in the analytical engine.

“Arrangements analogous to those just described have been introduced into the Analytical engine.

It contains two principal species of cards: first, Operation cards, by means of which the parts of the machine are so disposed as to execute any determinate series of operations, such as additions, subtractions, multiplications, and divisions; secondly, cards of the Variables, which indicate to the machine the columns on which the results are to be represented.

The cards, when put in motion, successively arrange the various portions of the machine according to the nature of the processes that are to be effected, and the machine at the same time executes these processes by means of the various pieces of mechanism of which it is constituted.

In order more perfectly to conceive the thing, let us select as an example the resolution of the two equations of the first degree with two unknown quantities:-

         mx + ny = d

         m’x + n’y = d’

Stay tuned to the voice of an average story storytelling chimpanzee or login at http://panarrans.blogspot.com
                              
Good night mon ami and my fellow cousin ape.
                           
  
                

             












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Another great educator and a teacher that I am aware of is Professor Subhashish Chattopadhyay in Bangalore, India.

While I narrate stories, Professor Subhashish an electronic engineer and a former professor at BARC, does and teaches real mathematics and physics.

He started the participation of Indian students at the International Physics Olympiad.

Do visit him here:


All his books can be downloaded for free through this link:


For edutainment and English education of your children, I recommend this large collection of Halloween Songs for Kids:



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